20436780 has 192 divisors, whose sum is σ = 74511360. Its totient is φ = 4064256.

The previous prime is 20436751. The next prime is 20436791. The reversal of 20436780 is 8763402.

20436780 is nontrivially palindromic in base 11.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 103642 + ... + 103838.

It is an arithmetic number, because the mean of its divisors is an integer number (388080).

Almost surely, 2^20436780 is an apocalyptic number.

20436780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20436780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37255680).

20436780 is an abundant number, since it is smaller than the sum of its proper divisors (54074580).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20436780 is a wasteful number, since it uses less digits than its factorization.

20436780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 248 (or 246 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 30.

The square root of 20436780 is about 4520.7056971230. The cubic root of 20436780 is about 273.4035545670.

The spelling of 20436780 in words is "twenty million, four hundred thirty-six thousand, seven hundred eighty".